From Nookipedia, the Animal Crossing wiki
The Ocean Sunfish (マンボウ, Manbō) is a fish that appears during the summer months, from 4 am to 9 pm. It is the least valuable member of the shark family. Its shadow, like all other members of the shark family, is huge and has a fin protruding from the ocean. It can be sold for 4,000 Bells.
Donating to the Museum
In Wild World
"I understand that ocean sunfish are edible, but... I've also heard that unless it's incredibly fresh, it tastes rather foul. As such, it's usually only eaten where it's caught!"
The ocean sunfish will be found in the second room in the ocean tank.
In City Folk
"...The ocean sunfish, it turns out, is related to the blowfish! Shocking, no? Absolutely mind-boggly! The resemblance is quite strong in its little mouth and round body... Seems rather blowfishy to me! ...There's something almost therapeutic about watching its slow, dull movements and vacant expression."
It can be found in the tank at the back of the aquarium, with other ocean fish.
In New Leaf
An information board in the aquarium displays a description of the ocean sunfish:
"Ocean Sunfish are a relative of blowfish that can reach up to two tons in weight. Lacking a tail fin, they cannot swim particularly quickly, which is an odd bit of anatomical detriment. The number of eggs they can lay is the most in the world at over 300 million. However, out of that 300 million, only one or two fish will ultimately survive. Ocean sunfish sometimes like to bob up and down on the surface of the ocean. This gives them the appearance they're sunbathing, which helps to make them a popular breed of fish."
The real ocean sunfish is the type species of its family, Molidae. It can be found all over the world in temperate or tropical seas. It is huge, being up to 3.2 meters tall and weighing over one metric ton. It is the heaviest known bony fish. They are gentle giants and are very curious. Their brain is the size of a nut. When resting the ocean sunfish will lay down on its side just below the ocean's surface, looking like it is dead. Their diet consistes of mostly jellyfish, and sadly, many ocean sunfish die when they choke on plastic bags that look like jellyfish. Ocean sunfish are unable to fully close their mouths. Ocean sunfish are often victims of skin parasites, and they will invite small fish and even birds to clean their skin.
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